Anaerobic Ammonium Oxidation (Anammox) for Nitrogen Removal Abdullah Matalgah Mentor: Dr. Reyes Sierra Dept. Chemical and Environmental Engineering April, 14, 2018
Our Objective is to Remove Ammonium
Ammonium Issues: Ammonium-NH4+ in water causes public health threats and fish toxicity NH4+ is present in municipal wastewater at high concentration The conventional method of NH4+ removal is energy intensive with high C-footprint
Solution: Anammox: NH4+ + NO2- → N2 + 2H2O The Anammox process removes NH4+ more economically with less C-footprint Anammox: NH4+ + NO2- → N2 + 2H2O The performance of the Anammox process will be investigated in an expanded granular sludge bed (EGSB) bioreactor
Mechanisms: Double Time: Anammox: 9-10 days E-Coli: 20 minutes
EGSB Bioreactor
EGSB: Expanded Granular Sludge Bed The reactor was continuously fed with synthetic wastewater The performance was monitored by measuring the Nutrient-N (NH4+ & NO2-) in influent and effluent samples using ion chromatography Also, the volume of N2 gas produced was measured over time
Twin Nursing Reactors: Temp: 30°C HRT: 0.21 day Influent: N2 bubble Twin Nursing Reactors: Temp: 30°C HRT: 0.21 day Influent: Ammonium: 502 mg/L Nitrite: 1440 mg/L
Average Removal (g/Lreactor -day) N2 gas production (g/Lreactor -day) (IC) NH4+ 1.59 ± 0.30 NO2- 4.78 ± 0.71 N2 gas production (g/Lreactor -day) (Gas Meter) Expected 2.52 Measured 1.54
Average Removal (g/Lreactor -day) N2 gas production (g/Lreactor -day) (IC) NH4+ 1.56 ± 0.22 NO2- 4.92 ± 0.74 N2 gas production (g/Lreactor -day) (Gas Meter) Expected 2.47 Measured 2.46
Anammox Activity Bioassay
Batch Activity Test To determine the max. specific anammox activity of the biomass, i.e., amount of N2 gas per gram of dry biomass and per day. The experiment is performed in a 160ml serum flask 100ml synthetic wastewater medium 60ml Helium gas 0.5g biomass Using Gas Chromatography, the N2 content in gas samples is evaluated six times, once per hour.
Anammox Activity Bioassay Basal medium He He Biomass taken from a granular enrichment culture (Brocadia spp.) Biomass Bottle Vol. = 160 ml Liquid Vol. = 100 ml (Total) Liquid & headspace flushing with He (6 min each) Addition of substrate NH4+ = 5.4 mM NO2- = 7.1mM
Conclusions The continuous Anammox bioreactors provided high NH4+ and NO2- removal efficiency (93% on average). Based on the batch bioassays, the max. specific activity of the biomass was 1 g N/(gram dry biomass x day). Due to the advantages of the Anammox Process, Pima County Water Reclamation Department is interested in implementing this process.
Acknowledgements I would like to thank Dr. Reyes Sierra for introducing me to the water treatment field which made me more determinant of my future careers. Special Thanks to Dr. Guangbin Li, Nivrutti Lakhey, Derek Swartzendruber, and Hezhou Ding for teaching and assisting me in the lab work. Also, Thanks to NASA Space Grant for its support during this internship experience.
Appendices
Mechanisms: Influent: 1 NH4+ +1.32 NO2- +0.066 HCO3- + 0.13 H+ Effluents: 1.02 N2 +0.026 NO3- +2.03 H2O +CH2O0.5N0.15 https://en.wikipedia.org/wiki/Anammox
https://www.ugent.be/bw/biosysteemtechniek/en/research/biosystems-control/completed_research_projects/research-castrobarros.htm
Sealing Cap Serum flask Anammox Bacteria Medium Helium gas